This invention generally pertains to a system for delivering chemicals such as tetraethylorthosilicate (TEOS) from bulk delivery canisters to manufacturing process tools such as chemical vapor deposition (CVD) devices.
The production of electronic devices such as integrated circuits is well known. In certain steps in such production, chemical may be fed to certain process tools which use the chemical. For instance, a CVD reactor is commonly employed to generate a layer of a given material, such as a layer of amorphous silicon oxide from TEOS. Historically, the TEOS was fed to the CVD reactor via bulk delivery cabinets utilizing 5 or 10 gallon canisters. The increase in consumption of TEOS has increased significantly due to increased metal layers and 300 mm processes. The more complex processes on larger wafers have also put pressure on the economics of each layer. 200 liter canisters allow for economies of scale savings that are passed on to the customer. In addition, the larger bulk canister reduces the number of container changes, labor, and shipping costs. In view of an increase in TEOS requirements for manufacturing operations, a need exists for a system which supplies an uninterrupted stream of chemicals to multiple process tools. Similarly, since existing fabrication facilities routinely change out canisters at each cabinet, and since each replacement results in potential contamination of the system, it would be desirable to reduce the number of contamination points.